Automatically operative valve



Sepia 19, i933, R, J. DOUGHERTY 1,927,259

AUTOMATICALLY OPERATIVE VALVE Filed June 18, 1928 FI J I JZ 9 `I VSN VrJ0 Patented Sept. 19, 1933 PATENT OFFICE.

1.927.259 'AUTOMATIGALLY orEnATlvn VALVE Robert J. Dougherty, Ambler,Pa., signor to John Wood Manufacturing Company, Conshohocken, Pa., acorporation Pennsylvania Application June 18,1928. sei-m1 N6. 236,087

1 claim. (ci. la7-'153)' i The improvement in flow-controlled gas waterheaters disclosed in this case is claimed in my copending applicationSerial No. 364,600 llled May 20, 1929.

5 My invention is particularly applicable to gasfred water heaters suchas described in application Serial No. 171,237 filed February 26, 1927by Victor Mauck for Letters Patent of the United States, andparticularly a house heating system including such a heater withthermostatically controlled valves such as described in Victor Maucksapplication Serial No. 187,590 led April 29, 1927 for Letters Patent ofthe United States.

Such heaters include cellular units comprising congeries of primarilycylindrical thin copper tubes, the ends of which are expanded andsoldered together, so that the tubes alford passageways for products ofcombustion to heat water contained in the space around said tubes. Insuch heating systems, it is necessary to forcibly circulate the water toprevent accidental overheating of the soldered portions of such unitsand consequent disintegration thereof, and it is preferable to eect suchcirculation by an electrically operated pump. However, such pumps are ofcourse, liable to be rendered temporarily inoperative by abnormalcondition of their supply circuit, ror instance, by the blowing of afuse. Unless means are provided to practically instantaneously shut oithe supply of gas to the burner of such a water heater upon cessation ofoperation of the means for circulating the Water, serious I damage tothe heater may result, for, at its maximum consumption of gas, such aburner is capable of melting the solder :from the joints in theportiono'f such a heater unit adjacent the burner in approximately tenseconds after cessation of operation of the pump.

l have not been able to nd upon the market any thermostaticallycontrolled means for shutting off the gas supply to such a burner Withinthe time thus limited. Therefore, the general purpose and eiect of thisinvention is to provide means which are practically instantaneouslyoperative to shut oi or shut down to a minimum, the supply of gas to aburner as the consequence of cessation of operation of a pump embodiedin such a heating system as above contemplated. However, it is obviousthat my invention is of more general application and, therefore, I donot desire to limit myself to the specic embodiment thereof hereindescribed.

As hereinafter. described, lmy improved valve includes a disk incooperative relation with an annular seat and held between two metallicbellows which are subjected to internal pressure from respectivelyopposite sides of the pump; said valve being held off its seat to permitthe flow of gas thru the latter when the pump is not operating but beingclosed upon its seat to 00 shut off the supply of gas, when the pump isoperating.

My invention includes the various novel features of construction andarrangement hereinafter'more denitely specified. 05

In said drawing; Fig. I is a longitudinal sectional view' of anautomatically operative valve embodying my invention.

Fig. II is a diagram showing the essential elements of a gas-fired waterheating system embodying elements with which said valve is adapted tocooperate to control the supply of gas to the heater burner.

Referring to Fig. I; the cylindrical-tubular casing 1 has gas ports 2and 3 extending thru its side 75 wall at respectively opposite endsthereof, and the annular valve seat 5 intermediate of said ports, incooperative relation with the valve disk 6 which is normally held oi itsseat by the corrugated cylindrical tubular bellows 7 and 8, which extend80 upon respectively opposite sides thereof in coaxial relationtherewith. Consequently, said casing 1 normally establishescommunication between said gas ports 2 and 3 thru said seat 5. The outerends 85 of said bellows 7 and 8 are respectively rigidly connected withplugs 9 and l0 which have screw threads 1l and l2 respectively engagingthe opposite ends of said casing 1. The inner ends of said bellows 7 and8 are respectively rigidly con- 90 nected with disk heads 14 and l5.Said head 15 has the screw threaded socket 17 for axially adjustable anddetachable engagement with the stem 18 of said valve disk 6 so that thelatter is rigidly connected with said bellows head 15. Said valve 6 hasthe axially opposite stem 19 tted in the seat 20 in the bellows head 14;so that said valve disk 6 is resiliently supported in coaxial relationwith its annular seat 5 but is axially adjusted so that it is normallyheld off said seat, as shown.

As hereinafter described, said bellows 7 is subjected to internalpressure by water from the intake conduit 22 of the pump 23, shown inFig. II, whereas, said bellows 8 is subjected to internal 705 pressureby water from the discharge conduit 24 of said pump; so that when saidpump is operating, the internal pressure in the b ellows 8 exceeds thatin the bellows 7 and the valve disk 6 is closed upon its seat to thusshut off communication besaid casing.

Referring to Fig. H; 26 indicates the main gas burner of the heaterabove contemplated, which is supplied with gas thru the conduit 27, andthe function of said valve 6 in the embodiment shown in Fig. II is tostop the supply of gas thru said conduit 27 when said pump 23 is for anyreason stopped.

The conduit 28 leads from a municipal gas main or other source of fuelgas under pressure and is connected with the casing 29 below the seat 30for the main diaphragm valve 3l, which is carried by the flexiblediaphragm 32 so that it normally gravitates to closed position, toprevent the flow of gas thru said conduit 27 to said burner 26.

However, said gas conduit 28 is continually in communication with thegas conduits 33 and 34:, which are connected with said diaphragm valvecasing 29 merely for convenience of assembly. Said conduit 33 leadsdirectly to the pilot burner 35 which is normally lit. Said conduit 34'.leads directly to the port 2 in the automatic valve casing l aforesaid;so that the space at the right hand side of the valve disk 6 in Fig. Iis continually directly connected with the gas supply conduit 28. lliheport 3 of said valve casing l is connected with said main diaphragmvalve casing 29, above the diaphragm 3l in the latter, by the conduits36 and 37; so that, when said valve 6 is open, which is its normal,idle, condition; said diaphragm valve 3l is subjected, upon both sides,to the normal pressure of the gas supplied thru the conduit 28, and isthen held closed not only by gravity, but by reason oi the greater areaci said diaphragm 32 exposed to said gas pressure above thanbelow saidseat 30.

Said gas conduit 37 is in. communication with the switch diaphragmcasing 39 below the erdble diaphragm do therein, so as to normallyuplift said diaphragm when the valve 6 is open. Said diaphragm 40 isoperatively connected with the 'electric switch lever di which is incooperative relation with the switch terminals d2 and 43 so that, whensaid diaphragm l0 lowers, said terminals d2 and t3 are permitted to comein contact and close the circuit between the conductors d5 and 46 tothen energize the electric motor t7 which operates the pump 23.

lin order to automatically initiate the operation oi said main burner 26and water pump 23; li provide the gas bleed pipe dit thru which the gasfrom the conduit 37 may escape into the conduit 34 leading to the pilotburner 35, under control oi' three thermostatically operative valves, towit, nrst, the valve which has the thermostatic tube 5l. extending inthe hot water hitting 52 oi the heater system; which valve is set toclose at, say, 266 F. Second, the valve 5d having the thermostaticelement 55, is adapted to close at some room temperature, say 76 F.,and, third, the safety valve 57 having the thermostatic element 56 andadapted to close when the temperature local to the burner 26 falls belowa predetermined degree. However, said thermostatic element 58 is adaptedto maintain said valve 57 open whenever the pilot burner 35 is lightedso as to maintain the name 59.

in order to insure suiiicient gas pressure in said conduit 37 to upliftthe switch diaphragm lo when the valve 6 is closed; i provide said maindiaphragm valve 3i with a bleed port 69 thru which sucient gas issupplied to the conduit 37 to uphold said switch diaphragm i0 undernormal idle conditions. i also prefer to include in said Y neonato tweenthe gas ports 2 and 3 at opposite ends of conduit 3'! a ntting 6lconstrict the edective area o said conduit to such a degree to permitthe now therethru oi the vole of gas admitted thru the bleed port 89,but oering sumclent resistance to the large volume of gasirom theconduit 36 to insure instantaneous closure of the diaphragm valvel A3lwhenever said dierential valve 6 is opened.` Y'

The normal cycle of operation is as follows: If the temperature of theroom in which said valve 5d is mounted falls below the temperature forwhich that valve is set; said valve 54 opens and, providing that thepilot burner 35 is lighted so that the valve 5'1 is held open, and thatthe temperature of the water in the system and in the container 452 isnot above the critical temperature so that said valve 56 is open; thegas pressure below the switch diaphragm 4&0 is relieved by the escape ofgas thru the bleed pipe 48 and' said diaphragm falls and edects theclosure of the circuit 45, d6 of the electric motor 47 and thus startsoperation oi the pump 23 to begin the circulation of water in thesystem. As

soon as such circulation is established, the dier ence in pressure ofthe water in the bellows 'i and a closes said valve 6, and gas nowthrough said valve to the space in the casing 29 above the diaphragmvalve 3l being thus stopped; said valve 3i is lifted by the normal gaspressure below it and gas is thus admitted to the main burner 26 thruthe valve seat 30 in the main diaphragm valve casing 29. The gas thussupplied to the burner 26 is, oi' course, ignited by the flame 59 of thepilot burner 35, and the heater 63 continues to operate until either ofthe automatic control valves 50 or 5i is closed, respectively by rise oftemperature of the water in the container 52 above the criticaltemperature, or rise of teinperature of the atmosphere in the room localto the valve 54.*-, Closure of either of said valves 5o or 5d stops theescape of gas from the bleed pipe et, and the gas admitted thru thebleed port 60 uplifts said switch diaphragm d6, breaking the circuit oithe motor d?- and stopping the operation of the pump. The instant thepump stops, said valve 6 (which has been held closed by the pressure ofwater incident to the operation of the punipJ ope full gas pressureabove the main diaphragm valve 31 closing the latter and thusinstantaneously stopping the supply of gas to the main burner 26 andthus preventing any danger of overheat ing and disintegrating the watercontainers 63 above the same.

However, although my improved automatically operative dierential valvewas designed for inclusion in the complex system indicated in Fig. H; itis susceptible or use in other embodiments. Moreover, it may be soadjusted that it is normally shut and may be opened by difference oipressure in the bellows and 8 instead oi being closed by difference inpressure in said bellows.

"therefore, i do not desire to limit myself to the precise details ofconstruction, arrangement, or method of operation herein set forth, asit is obvious that various modifications may be made therein withoutdeparting from the essential fea tures of my invention, as deiined inthe appended claim.

i claim:

in an automatically operating valve structure; the combination with atubular casing having ports extending thru the circerence thereof thusadmitting the transversely to the axis of the casing and in spacedrelation; an annular valve seat rigidly connected with said casing,between said ports; screw plug closures respectively tted to theopposite ends of said casing; corrugated metallic bellows respectivelyrigidly connected at their outer ends to said screw plugs and havingclosure heads at their inner ends, and adapted to exclude the fluid insaid casing from said bellows; a valve carried by and between saidbellows heads and continually in contact therewith and tted to close onsaid seat and prevent communication between said ports; said bellowsadapted to continually press said valve in respectively oppositedirections; said plugs having fluid ports opening thru them into therespective bellows; whereby said valve is held stationary when the uidpressure in said bellows is substantially equal, and said Valve isshifted with respect to its seat when the uid pressure in one of saidbellows exceeds that in the other; including an axial pivotal connectionbetween said valve and one of said bellows heads; and a screw thread onsaid valve; whereby said valve may be freely rotated in continualcontact with said head and is adapted for axial adjustment,independently of any fluid pressure.

ROBERT J. DOUGHERTY.

